This invention relates to an improved golf club head for enhancing a directional stability of a ball.
Generally, a head of an iron club is cast of metal such as soft iron or stainless steel, and a hosel portion, a sole portion, a face portion and so on are formed integrally with the club head. In this type of head, a sweet spot is enlarged by distributing the weight over a peripheral portion of a back side, and it is known that a moment of inertia is increased during the swing to enhance the directional stability of a ball.
Therefore, there has been proposed a golf club head as disclosed in Japanese Utility Model Examined Publication No. 3-23262 and shown in FIGS. 10 and 11, in which a weight member 3 of a horseshoe-shape, formed of a material greater in specific gravity than a head body 1, is secured to a peripheral portion of the head body 1. There has also been proposed a golf club head as disclosed in Japanese Utility Model Unexamined Publication No. 60-97158 and shown in FIGS. 12 and 13, in which a cavity (recess) 11 is formed in a back side 9 of a head body 7 except for a peripheral portion 10 thereof, and a weight member 15, made of a material greater in specific gravity than the head body 7, is secured to a step portion 13 formed in the back side of the peripheral portion 10.
However, in the head 17 shown in FIG. 10, although the weight member 3 is secured to the peripheral portion of the head body 1, the central portion of the head body 1 remains thick as shown in FIG. 11, and therefore the weight of the head 17 could not be sufficiently distributed over the peripheral portion of the back side.
In the latter head 19 shown in FIG. 12, the cavity 11 is formed in the back side 9 of the head body 7, and the weight member 15 is secured to the peripheral portion 10 of this back side. However, since the thickness of the head body 7 is increasing progressively toward a sole 21, the weight could not be sufficiently distributed over the peripheral portion of the back side 9 as is the case with the above conventional construction.
And besides, since the amount of projection of the peripheral portion 10 of the back side 9 is small, the weight member 15 can not be secured thereto in a large amount, and also in the construction in which the weight member 15 is secured to the back side of the peripheral portion 10, the weight could not be sufficiently distributed over the peripheral portion 10 of the back side 9. Thus, this and other problems have remain unsolved.